The present disclosure is related to wellbore equipment and, more particularly, to systems and methods of orienting wellbore tubulars using gravity.
In the oil and gas industry, hydrocarbons can be produced through relatively complex wellbores traversing one or more subterranean formations. Some wellbores can be multilateral wellbores, where one or more lateral wellbores extend from a parent (or main) wellbore. Multilateral wellbores often include one or more windows or casing exits provided on downhole wellbore tubulars that allow corresponding lateral wellbores to be formed. In order to accurately orient a multilateral window within the wellbore, measuring while drilling (MWD) tools or other common pressure-pulsing orientation indicating devices have been used. At increased depths, however, pressure pulses generated by conventional MWD tools become increasingly attenuated when the return flow path is restricted, such as in an annulus between an inner work string and an outer casing or liner string. As a result, a significant amount of pressure noise can be introduced into the system due to varied restrictions to flow in the return flow path. These conditions make the data transmitted by pressure pulses difficult to detect and interpret at a surface location.
Typical MWD tools also cannot be cemented through and they are too valuable to be drilled through. In addition, MWD tools do not provide for passage of plugs therethrough for releasing running tools, setting hangers and packers, etc. Moreover, if an MWD tool must be separately conveyed and retrieved from a well, additional time and expense are required for these operations. In addition, conveyance of MWD tools into very deviated or horizontal wellbores by wireline or pumping the tools downhole presents a variety of additional technical difficulties.